So, Your Doctor Thinks You May Have a Thyroid Disorder -- Now What?

An Overview of Common Thyroid Tests

Finding out that your thyroid may not be functioning properly can be a disorienting and emotionally draining experience. This sense of feeling overwhelmed and confused can sometimes be made even worse by the battery of tests, lab procedures, and other diagnostic assessments that follows a preliminary diagnosis of thyroid-related problems.

Once your doctor has determined that the signs and symptoms you’ve been experiencing may be linked to your thyroid, the next step will be assessing the health and performance of your thyroid gland using a number of advanced diagnostic procedures.

Because thyroid disorders can encompass such a broad range of illnesses, diseases, and conditions, it is likely that you will be subjected to a sizable number of diagnostic tests. In order to pinpoint the precise nature and extent of the problem, your doctor may arrange a full slate of procedures, ranging from blood work to advanced imaging of the thyroid gland.

It’s likely that the less that your doctor knows about your thyroid disorder, the more tests he or she will schedule. This week, we’ll take a look at some of the most common tests that are used to gauge thyroid health, function, and disorders.

Blood Tests

Because a dysfunctional thyroid gland can impact the level of hormones in your blood, blood tests are often an important component of the diagnostic process. Here are some common blood tests used to help identify possible thyroid problems.

• T3 levels - Blood tests are often used to determine the level of thyroid hormone triiodothyronine in the bloodstream.

• FTI or FT4 - These tests are performed in order to determine the level of the thyroid hormone thyroxine that is in the bloodstream. Specifically, these tests focus on quantifying the small amount of the T4 hormone that is unattached to blood cells.

• Total T4 - This blood test shows the total level of thyroxine in the bloodstream, quantifying both attached and unattached cells.

• Thyroid antibodies test - If an autoimmune disorder such as Grave’s disorder is suspected, this blood test is used to determine whether the body’s immune system is attacking the thyroid gland.

• Thyroglobulin levels - This procedure is typically used in the diagnosis and management of thyroid cancer.

Radioactive Iodine Testing

These tests make use of the unique iodine-absorbing properties of the thyroid gland to measure thyroid function. They are usually only performed on patients who are suspected to be hyperthyroid, or when a preliminary diagnosis of thyroid cancer has been made. They involve ingesting a very small dose of radioactive iodine and viewing its path in the body using advanced imaging techniques.

• Radioactive Iodine Uptake Test - This test is used to help doctors achieve a clearer understanding of the source of your thyroid-related symptoms. It can help them to determine whether you are hyperthyroid and the degree of thyroid hyperactivity. It can also allow doctors a closer look at a nodule or growth on the thyroid gland. Lastly, in patients who have been diagnosed with thyroid cancer, this test can show whether the cancer has spread beyond the thyroid gland.

• Thyroid Scan - In some cases, thyroid scans are performed as part of a radioactive iodine uptake test, but they can also be performed as stand-alone assessments. If it is not done in tandem with a radioactive iodine uptake tests, thyroid scans are usually used to observe and diagnose thyroid nodules or growths.

Other Thyroid Imaging Procedures

If a growth or nodule has been detected on your thyroid, your doctor may choose to order several imaging procedures to get a better look at the abnormal tissue and better determine its origins.

• Ultrasound - This painless, non-invasive imaging procedure will provide doctors with a highly detailed snapshot of your thyroid, allowing them to get a closer look at any suspect growths and nodules. The ultrasound, also known as a sonograph, uses sound waves to produce images of internal organs.

• Computerized tomography - More commonly known as CAT scans or CT scans, this imaging technique relies on the same basic technology that powers standard x-rays, although it is applied in a slightly different way. These images can help doctors get a wider look at the entire neck area, which can sometimes be helpful in diagnosing the size and extent of thyroid cancers and malignant growths.

• Magnetic resonance imaging - This relatively newly developed imaging technique draws on the power of magnetism to produce crystal-clear images of internal organs, tissues, and musculoskeletal structures. This test is typically used only if thyroid growths or tumors are believed to be present.

They say that knowledge is power, and when it comes to medical procedures, having a basic understanding of the nature of the tests that are being performed can make all the difference in the world. If you are unclear about the purpose or nature of any of the diagnostic procedures your doctor has arranged, don’t hesitate to request more information. Remember, the only stupid question is the one that remains unasked!

For Further Reading

• http://www.endocrineweb.com/tests.html

• http://thyroid.about.com/cs/newsinfo/l/bltest_values.htm